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Consumers are predisposed to spend more when their brains are in "down time" mode.

“Shop ‘til you drop” is so last-millennium. The proliferation of smartphones and tablets means that shoppers today are clicking “buy” even after they’ve dropped — into bed or the bathtub. 

This is terrific for retailers, since consumers are predisposed to spend more when their brains are in “down time” mode. But for those customers, their relaxation-induced splurges might lead to some buyer’s remorse. 

More than half of smartphone and tablet owners use their devices in bed, and about a quarter do in the bathroom, according to a Nielsen study conducted last year. It’s a safe bet that a number of them are shopping, according to a recent survey out of the U.K.

A division of online retailer Shop Direct Group asked 1,000 customers where they shopped: 43 percent said in bed, 18 percent said on the toilet and 14 percent said in the bath.

 Shoppers today do more research — checking comparison-shopping sites, reading user reviews and so on —  before making a purchase, said Heidi Cohen, president of Riverside Marketing Strategies. “What’s happened today with shopping is there’s a lot more time spent and there’s a lot more steps.”

 With only so many hours in the day and mobile devices that people carry practically everywhere, there’s some inevitable spillover of that pre-shopping into people’s private time.

“Convenience is also playing a part,” Sarah Quinn, marketing manager at On Device Research, said via email. “They have their mobile switched on and it’s usually with them all the time, so they don’t need to wait until the evening when they’re at home to switch on their PC.”

A study of American mobile shoppers conducted by On Device in conjunction with the Interactive Advertising Bureau found that nearly half of purchases take place at home.

But sinking into a bubble bath to do some online shopping might not be the best idea for someone trying to stick to a budget, and not only because they’ll be stuck replacing it if it falls in the water. Michel Pham, a professor at at Columbia University’s Business School, found that shopping while unwinding can be an expensive hobby. 

In Pham’s experiments, subjects in a state of relaxation thought items were worth more than they actually were and were willing to pay as much as 15 percent more for things than people in a neutral frame of mind.

“This effect seems to be caused by differences in relaxed and non-relaxed individuals’ mental construals of the value of the products,” he wrote. When relaxed, shoppers think about how enjoyable the purchase will be, rather than consider practicalities like price.

Sites are catching on and taking advantage of this, sending out emails or social media promotions at hours when customers are more likely to be unwinding — possibly with a glass of wine or a cocktail, which lowers inhibitions further. Andy Page, president of online flash sale retailer Gilt Groupe, told the New York Times last year that his site added 9 p.m. sales to take advantage of this buying behavior.

This type of shopping is likely to be more pleasant," Lars Perner, a marketing professor at the University of Southern California, said via email.  "People will tend to be less critical while in a good mood, meaning that people may be more likely to buy things that they would be more likely to resist during ordinary shopping trips."

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